The Effect of Vascular Risk Factors on the Efficacy of Rivastigmine Patch and Capsule Treatment in Alzheimer's Disease

BACKGROUND: Vascular risk factors (VRF) may influence response to rivastigmine in Alzheimer's disease (AD). METHODS: AD patients who participated in a randomized, double-blind, placebo-controlled trial of rivastigmine patch and capsule treatment were stratified by baseline VRF status. Treatment response was evaluated using the AD Assessment Scale-cognitive subscale (ADAS-cog), AD Cooperative Study-Clinical Global Impression of Change (ADCS-CGIC) and the AD Cooperative Study-Activities of Daily Living (ADCS-ADL) scale. RESULTS: ADAS-cog scores significantly improved in all rivastigmine-treated patients (p < 0.05 vs. placebo), except 9.5 mg/24 h patch-treated patients with VRF, and were significantly affected by VRF status in the study population as a whole. Significant benefits were seen on the ADCS-ADL in 9.5 mg/24 h patch- and capsule-treated patients with, but not without, VRF. The ADCS-CGIC significantly improved in capsule-treated patients with, and patch-treated patients without VRF. Although non-significant, patients without VRF showed an apparent faster rate of placebo decline. CONCLUSION: VRF may influence AD progression and response to rivastigmine.